How do you factor $x²+8x+7$ ?

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Answer 1 · 2015-11-07T23:14:33

$(x+1)(x+7)$

To quickly factor it, we want to find two numbers that add up to $8$ (the coefficient in front of x) and multiply to $7$ (the constant).

You might quickly see that the numbers we want are $1$ and $7$ .

Next, simply write 2 pairs of parenthesis and put " $x+$ " and the two magical numbers we just found...

$(x+1)(x+7)$

Notice if you were to FOIL this out, you would get the original expression. In fact, what we just did was FOIL-ing backwards.

Answer 2 · 2015-11-07T23:14:45

$x^2+8x+7=(x+1)(x+7)$

$x^2+8x+7$

Find two numbers that when added equal $8$ and when multiplied equal $7$ . The numbers $1$ and $7$ meet the criteria.

$x^2+8x+7=(x+1)(x+7)$

How do you factor x²+8x+7x²+8x+7?